Expanding-pulley.



No. 64|,28I. Patented Ian. I6, I900.

T. A. EDISON &. C. M. JOHNSON.

EXPANDING PULLEY..

(Application filed Apr. 24, 1899.) (No Model.)

3 Sheets-Sheet l.

Patented Ian. l6, I900. T. A. EDISON &. C. M. JOHNSON.

EXPANDING PULLEY.

(Application flied Apt. 24, 1899.)

3 Sheets-Sheet 2.

(no Model.)

Patented Jan. I6, I900. T. A. EDISON & C. M. JOHNSON.

EXPANDING PULLEY.

ApplicMinn filnd Apr. 24. 1899.1

3 Sheets-Sheet 3 (No Model.)

W1tnesses. 0 I11 ven tors- CAM v I MM- 2; I fiwuLum/fi A" AEN tries.-

THOMAS A. EDISON, OF LLEIVELLYN PARK, NE\V JERSEY, ANT) CHARLES M.

JOHNSON, OF REDHILL, ENGLAND.

EXPANDING PU LLEY.

SPECIFICATION forming part of Letters Patent No. 641,281, dated January16, 1900.

Application filed April 24, 1899.

T 0 all whom it may concern.-

Be it known that we, THOMAS A. EDISON, residing at Llewellyn Park, inthe county of Essex and State of New Jersey, and CHARLES M. JOHNSON,residing at Redhill, in the county of Surrey, England, citizens of theUnited States, have invented certain new and useful Improvements inExpanding Pulleys, of which the following is a specification.

Our invention relates to various new and useful improvements inexpanding pulleys adapted to convert a uniform velocity of adrivingshaft into varying velocities of a driven belt or to convert theuniform velocity of a driving-belt into varying velocities of a drivenshaft.

The object of the invention is to provide an improved construction ofexpansible pulley which will he possessed of great rigidity and whereinthe working diameter may be quickly and easily varied.

The invention preferably comprises two of the improved expansiblepulleys arranged on parallel shafts and connected by a belt, wherebypower will be transmitted from one shaft to the other. When twoexpansible pulleys are employed, the invention comprises devices forsimultaneously varying their working diameters in inverse directions,whereby the relative speeds of rotation of the shafts will be changed.If a crossed belt is employed, when two expansible pulleys are used,with devices for simultaneously operating them, the belt will bemaintained uniformly tight irrespective of the changes in the diameterof the two pulleys, since the increase in diameter of one will exactlycompensate for the decrease in the diameter of the other.

The invention also comprises means for tightening the belt whennecessary and for keeping it in a tight condition.

In carrying out our invention we employ an expansible pulley comprising,essentially, two intercalated cones movable toward and away from eachother and each consisting of a series of ribs or bars which areconnected at their outer or enlarged ends to tapering sheaths, intowhich work the bars or ribs of the companion cone, and means beingprovided to shift the cones relatively. When the invention comprises apair of these ex- Serial No. 714,340. (No model.)

pansible pulleys arranged on parallel shafts, one conical section ofeach pulley will be stationary with respect to the shaft, the otherbeing movable longitudinally thereon, but rotating therewith. We employa rock-shaft extending at right angles to the driving and driven shaftsand carrying arms which are connected with the movable conical sectionof each expansible pulley. The movable section of one expansible pulleyis arranged with respect to the corresponding section of the other sothat when movement of both takes place in one direction by the operationof the rock-shaft the working diameter of one pulley will be increased,while the working diameter of the other will be decreased. Not only willthis provide for changes in the speed of the belt, but in effecting aspeed change the belt will be shifted always parallel to the plane ofits driving movement, whereby if a crossed belt is used it will alwaysbe maintained tight.

When the invention comprises additional means for tightening the belt,we hang the rock-shaft from the driving and driven shafts and supportone of the latter by a pair of links depending from a power-shaft orworkshaft, whereby the former may move radially with respect to theother. Power is communicated between these two shafts by suitablegearing which is unafiected by the radial movementsas,for example, bytwo engaging gears. In this way the two shafts carrying the expansiblepulleys may be moved laterally with respect to each other to secure theproper tension of the belt without afiecting the transmission of powereither to or from the expansible pulleys or to or from each other.

In order that our invention may be better understood, attention isdirected to the accompanying drawings, forming a part of thisspecification, and in which- Figure 1 is a plan of an apparatusillustrating an embodiment of our invention,showing two shafts carryingthe two conical pulleys with means for simultaneously adjusting them andshowing in dotted and full lines the extremepositionof the conicalsections. In this View the chain-line illustrates the position of thebelt when the expansible pulleys are in the position shown in fulllines, while the dotted line illustrates the position of the belt whenthe sections of the expansible pulleys are in the position shown indotted lines. Fig. 2 is a side elevation illustrating a power or workshaft and showing the preferred means for eifecting the adjustment ofthe belt; Fig. 3, a section on the line 3 3 of Fig. 2, showing only aportion of one of the expansible pulleys; Fig. 4, a longitudinal sectionthrough the shaft A of Figs. 1 and 2, and Fig. 5 a plan view showing theconical sections 0 and D relatively separated.

In all of the above views corresponding parts are represented by thesame letters of reference.

A and B represent the two shafts, the former being the driving-shaft andthe latter the driven shaft. Each shaft carries an expanding pulleyformed of two opposed conical members 0 D and E F. In the embodiment ofthe invention illustrated in the drawings each conical member is formedof a number of bars or ribs which constitute the conical surface, thebars of one member being intercalated between those of the other memberof the pulley, the points of intersection forming,substantially, aV-groove, at the bottom of which the belt or band engages. The cones arecarried upon their respective shafts in such a manner that one member ofeach pair is fixed thereupon and the other member capable of adjustmentby axial movement upon the shaft. The members C and Fin the present caseare adjustable, and the members D and E are stationary. The axialadjustment of the conical members 0 and F is in the example illustratedeffected simultaneously by connections operated from a rock-shaft G insuch a manner that the belt travels axially parallel to itself andremains uniformly tight for all the attainable velocity ratios of theshafts AandB,as will be presently explained.

Regarding the preferred constructional details of the expansiblepulleys, each set of the ribs or bars 0, D, E, and F is supported at itslarger circumference by a conical sheath C, D, E, and F, respectively.The sheaths of each conical member will, when the pulley is expanded,receive and cover the inner extremities of the companion members, aswill be obvious. The inner extremities of the bars or ribs 0 unite toform or are secured to a sleeve C and the inner end of the sheath 0 issupported bya boss 0 both the boss G and sleeve 0 being free to moveaxially upon the shaft A, but either or both being rotatively drivenfrom the shaft in any suitable way, as from a feather A. The sleeve()terminates at C in a collar, the purpose of which will be explain ed.The inner ends of the bars or ribs D of the other conical member uniteto form a boss D which is keyed or otherwise fixed to the shaft A, andthe other ends are secured to the sheath D, whose smaller diameter formsor is connected to the collar D The sleeve 0 works within the collar Dbut may be driven therefrom, if desired, by a key or feather a, as shownin Figs. 4: and 5. The bars 0 are thus driven from the shaft at the bossC and at the sleeve C through the feather A, and the bars D are driventhrough the boss D either alone or in connection with a drivingconnection from the sleeve C at the collar D The pulley carried by theshaft B is similar in construction to that on the shaft A, except thatthe bars E being fixed and the bars F adjustable axially the inner endsof the former terminate in a boss (not shown) fixed to the shaft insteadof in a movable sleeve, while the sleeveF at the small end of the sheathF is capable of axial movement, as is also a sleeve (not shown) in whichthe inner ends of the bars F terminate.

The adjusting device for shifting the movable sections of eachexpansible pulley with respect to the stationary sections thereofcomprises a rock-shaft G, operated by a hand-lever G and carrying asleeve H, splined to the shaft on a feather H and a second sleeve J,fixed to said shaft. Each of these sleeves carries a pair of arms H Hand J J, respectively. The arms H are pivoted to projections L on asleeve L, arranged to slide upon the shaft A, the latter rotating freelywithin it. The sleeve L engages the end of the collar 0 so as to impartaxial movement thereto without interfering with the rotation thereof. Ifdesired,an antifriction-bearing maybe interposed between the collar andsleeve. A

.similar connection is provided by a sleeve K,

having projections K, within which the arms J are pivoted, the saidsleeve K engaging with and moving the sleeve F of the movable member ofthe expansible pulley on the shaft B. The rock-shaft G will be thussupported from the shafts A and B through the links H and J. It isguided at its ends in bearings M and Q, as shown more particularly inFig. 3, whereby aslight rise and fall of the shaft will be permitted.The bearing-box for the rock-shaft G, working in the bearing M, is shownat M, Fig. 2. The shaft A in this instance is suspended by links 1) I),as shown in Fig. 4, from a power or work shaft 0, from which it isdriven or which it itself drives, preferably, by toothed gearing O ,asshown. By suspending the shaft Afrom the power or work shaft 0 by meansof links I) b, as explained, the shaft A may be swung relatively totighten or loosen the belt, the extreme positions of the shaft beingindicated in Fig. 2 by the reference-letters A and A The operation willbe as follows: The position shown in full lines in Fig. 1 illustratesthe pulley O D at its smallest and the pulley E F at its largestdiameter. If it is now desired to increase the velocity of the shaft Brelatively to that of A, assuming that the former is driven from thelatter, the lever G is moved so as to cause the cone member 0 toapproach the member D and the cone member F to recede from the member E.The extreme extentof this movement in this direction is shown in dottedlines in Fig. 1. The effect produced on the belt is to cause it totravel axially with the movable cones and parallel to its own plane ofrotation, and if it is a crossed belt it will remain uniformly tight atall velocity ratios of A and B, since the increase of the workingdiameter at one of the expansible pulleys is compensated by a decreasein the working diameter at the other pulley. If it is desired to adjustthe tightness of the belt, this may be effected by moving the shaft Aabout the center of the shaft 0, causing the shafts A and B to separate.In this movement the sleeve H will slide axially on the shaft G, whilethe inclination of the latter will be slightly changed, the end bearingsthereof working in the guides M and Q.

Having now described our invention, what we claim as new, and desire tosecure by Letters Patent, is as follows:

1. In an expansible pulley, the combination of a conical sectionfixedagainst lateral movement, a conical section movable laterally, saidconical sections comprising intercalated bars or ribs, a conical sheathfor the movable section inverted with respect to the same, and a sleeveto which the inner ends of the movable section are secured,substantially as set forth.

2. In an expansible pulley, the combination of a conical section fixedagainst lateral movement, a conical section movable laterally, saidconical sections comprising intercalated bars or ribs, a conical sheathfor the movable section inverted with respect to the same, a sleeve towhich the innerends of the movable section are secured, and means formoving said sleeve to vary the working diameter of the pulley,substantially as set forth.

3. The combination of two expansible pulleys, each comprising twointeroalated'conical sections, one section of each set being stationary,the stationary element of one set being reverse to that of the otherset, whereby when the movable sections of both sets are movedlongitudinally in one direction or the other the line of the workingdiameter of both pulleys will be shifted in parallelism, substantiallyas set forth.

4. The combination of two expansible pulleys, each comprising twointercalated conical sections, one section of each set being stationary,the stationary element of one set being reverse to that of the otherset, whereby when the movable sections of both sets are movedlongitudinally in one direction or the other the line of the workingdiameter of both pulleys will be shifted in parallelism, and means forsimultaneously shifting the movable section of each pulley,substantially as set forth.

' 5. The combination of two expansible pulleys, each comprising twointercalated conical sections, one section of each set being stationary,the stationary-element of one set being reverse to that of the otherset, whereby when the movable sections of both sets are movedlongitudinally in one direction or the other the line of the workingdiameter of both pulleys will be shifted in parallelism, a rockshaft,and connections between said rockshaft and the movable sections of bothpulleys, whereby the latter may be shifted simultaneously, substantiallyas set forth.

6. The combination of two expansible pulleys, each comprising twointercalated conical sections, one section of each set being stationary,the stationary element of one set being reverse to-that of the otherset, whereby when the movable sections of both sets are movedlongitudinally in one direction or the other the line of the workingdiameter of both pulleys will be shifted in parallelism, and means formoving the pulleys toward and away from each other for adjusting thetension of a belt between them, substantially as set forth.

7. The combination of two expansible pulleys, each comprising twointercalated conical sections, one section of each set being stationary,the stationary element of one set being reverse to that of the otherset, whereby when the'movable sections of both sets are movedlongitudinally in one direction or the other the line of the workingdiameter of both pulleys will be shifted in parallelism, a rockshaft,connections between the rock-shaft and the movable section of eachpulley for shifting the same, and means for moving one pulley laterallywith respect to the rock-shaft, whereby the tension of a belt may bevaried, substantially as set forth.

8. The combination of two expansible pulleys, each comprising twointercalated conical sections, one section of each set being stationary,the stationary element of one set being reverse to that of the otherset, whereby when the movable sections of both sets are movedlongitudinally in one direction or the other the line of the workingdiameter of both pulleys will be shifted in parallelism, and arock-shaft having arms which are attached to the movable section ofeachpulley and from which the rock-shaft will be supported, substantially asset forth.

9. The combination of two expansible pul leys, each comprising twointercalated conical sections, one section of each set being stationary,the stationary element of one set being reverseto that of the other set,whereby when the movable sections of both sets are moved longitudinallyin one direction or the other the line of the working diameter of bothpulleys will be shifted in parallelism, a rock-shaf t having arms whichare attached to the movable section of each pulley and from which therock-shaft will be supported, and end bearings for said rock-shaftpermitting vertical movements thereof, substantially as set forth.

10. The combination of two expansible pulleys, each comprising twointercalated conical sections, one section of each set being stationary,the stationary element of one set being reverse to that of the otherset, whereby when the movable sections of both sets are movedlongitudinally in one direction or the other the line of the workingdiameter of both pulleys will be shifted in parallelism, a rock-shafthaving arms which are attached to the movable section of each pulley andfrom which. the rock-shaft will be supported, end bearings for saidrock-shaf t permitting vertical movements thereof, and means forshifting one of the pulleys toward and awayfrom the other to adjust thetension of a belt, causing the ends of the rock-shaft to be moved in thebearings therefor, forth.

11. The combination of two expansiblepulleys, each comprising twointercalated conical sections, one section of each set being stationary,the stationary element of one set being reverse to that of the otherset, Whereby when the movable sections of both sets are movedlongitudinally in one direction or the other the line of the workingdiameter of both pulleys will be shifted in parallelism, a

substantially as set This specification signed and witnessed this 28thday of March, 1899.

CHARLES M. JOHNSON.

Witnesses to signature of Thomas A. Edison:

J. F. RANDOLPH, ARCHIBALD G. REESE. lVitnesses to signature of CharlesM. John son:

THOMAS JEFFREY, J AMES ALEXANDER.

